Reinforced impact beam

ABSTRACT

An impact beam having a polymer matrix and a metal reinforcing structure, the metal reinforcing structure including metal cords that can be made from metal elements having a diameter of 100 μm or more. The polymer matrix can include a thermoplastic material and/or a fiber material, and the metal can be steel, and the metal cords can be parallel to each other. The polymer matrix can include two or more layers that can be made from the same or different material, one of which can be positioned around the surface of the metal cords and can have a mechanical bond with the cord. The invention also includes a method of making the impact beam.

FIELD OF THE INVENTION

[0001] The present invention relates to impact beams and reinforcements,and a method to provide such impact beam. The invention further relatesto the use of an impact beam for support of bumpers of vehicles or forimpact reinforcing of parts of vehicles.

BACKGROUND OF THE INVENTION

[0002] Presently known composite impact beams comprise a polymer matrix,reinforced with glass fibers or other polymer fibers. An impact beam mayalso comprise metal parts, usually on the places where the impact beamreceives compression load during impact. U.S. Pat. No. 5,290,079 givesan example of such impact beam. In U.S. Pat. No. 5,290,079 the impactbeam also comprises a woven wire mesh, which is to improve the ductilityand flexibility of the impact beam.

[0003] Presently known composite impact beams in general have thedisadvantage that they tend to break or in two parts at the location ofimpact, or into several small particles which are projected towardsobjects which are in the periphery of the impact beam. This may causefurther damage to these objects.

SUMMARY OF THE INVENTION

[0004] It is an object of the present invention to provide an improvedimpact beam having increased resistance to impact. it is also an objectof the invention to provide an impact beam having a high-energyabsorption. It is an other object of the invention to provide an impactbeam having an improved integrity during and after impact.

[0005] An impact beam as subject of the invention comprises a polymermatrix and a metal reinforcing structure. According to the presentinvention, the metal reinforcing structure comprises one or more metalcords.

[0006] Preferably, the metal reinforcing structure comprises two or moremetal cords, the metal cord being preferably essentially parallel toeach other.

[0007] The wording “essentially parallel” is to be understood in a sensethat for each pair of metal cords, said cords being present one next tothe other, for each point of an axis of a first of these metal cords, arelated point of the axis of the second metal cord can be defined, whichpoint is the crossing point of the axis of the second metal cord, withthe plane through the point of the axis of the first metal cord andbeing perpendicular to the direction of the axis of the first metal cordat this point. The difference in direction of the axis's of the metalcords, in each pair of points is less than 25°, e.g. less than 15° oreven less than 10°, such as less than 5°.

[0008] An impact beam is characterized by a direction in which impactforces are expected to work on the impact beam. This direction ishereafter referred to as ‘impact direction’. Impact beams arecharacterized by an impact plane, being the plane perpendicular to thedirection of impact. One dimension of this plane is usually relativelylarge and is hereafter referred to as length of the impact beam. Thesecond dimension of the impact beam in this impact plane, is usuallymuch smaller than the length. This direction is hereafter referred to asheight of the impact beam. The dimension of the impact beam,perpendicular to impact plane is referred to as thickness of the impactbeam.

[0009] The metal cord of an impact beam as subject of the invention maybe provided in a direction essentially parallel to the length of theimpact beam.

[0010] Most preferably however, the metal cords are provided with acurved shape during molding of the impact beam as subject of theinvention. The curves have a bending radius in the plane perpendicularto the plane defined by the length and height, and parallel to thelength of the impact beam. The curvature preferably extends to the sideof the impact beam on which the impact force is to be expected to work.

[0011] The metal cord preferably used for an impact beam as subject ofthe invention, are of a type which can absorb relatively high amounts ofimpact energy but also other metal cords may be used.

[0012] Examples here are:

[0013] multi-strand metal cords e.g. of the m×n type, i.e. metal cords,comprising m strands with each n wires, such as 4×7×0.10 or 3×3×0.18;the last number is the diameter of each wire, expressed in mm.

[0014] compact cords, e.g. of the 1×n type, i.e. metal cords comprisingn metal wires, n being greater than 8, twisted in only one directionwith one single step to a compact cross-section, such as 1×9×0.18 or1×12×0.18; the last number is the diameter of each wire, expressed inmm.

[0015] layered metal cords e.g. of the l+m(+n) type, i.e. metal cordswith a core of l wires, surrounded by a layer of m wires, and possiblyalso surrounded by another layer of n wires, such as 2+4×0.18; the lastnumber is the diameter of each wire, expressed in mm.

[0016] single strand metal cords e.g. of the 1×m type, i.e. metal cordscomprising m metal wires, m ranging from two to six, twisted in onesingle step, such as 1×4×0.25; the last number is the diameter of eachwire, expressed in mm.

[0017] Open metal cords e.g. of the m+n type, i.e. metal cords with mparallel metal wires surrounded by n metal wires, such as disclosed inU.S. Pat. No. 4,408,444, e.g. a metal cord 2+2×0.25; the last number isthe diameter of each wire, expressed in mm.

[0018] All cords as described above can be equipped with one or morespiral wrapped wires to increase the mechanical bond of the cords in thepolymer matrix, and/or to bundle the n single parallel crimped ornon-crimped but plastically deformed wires if the cord is provided usingsuch parallel wires.

[0019] Preferably however, the metal cord used in the context of thepresent invention may be a metal cord with a high elongation atfracture, i.e. an elongation exceeding 4%, e.g. an elongation between 5%and 10%. High elongation metal cord has more capacity to absorb energy.Such a metal cord is:

[0020] either a high-elongation or elongation metal cord (HE-cords),i.e. a multi-strand or single strand metal cord with a high degree oftwisting (in case of multi-strand metal cords: the direction of twistingin the strand is equal to the direction of twisting of the strands inthe cord: SS or ZZ, this is the so-called Lang's Lay) in order to obtainan elastic cord with the required degree of springy potential; anexample is a 3×7×0.22 High Elongation metal cord with lay lengths 4.5 mmand 8 mm in SS direction;

[0021] or a metal cord which has been subjected to a stress-relievingtreatment such as disclosed in EP-A1-0 790 349; an example is a2×0.33+6×0.33 SS cord.

[0022] as an alternative or in addition to a high elongation metal cord,the metal cord may be composed of one or more wires which have beenplastically deformed so that they are wavy. This wavy natureadditionally increases the elongation. An example of a wavy pattern is ahelix or a spatial crimp such as disclosed in WO-A1-99/28547.

[0023] According to the required properties of the impact beam assubject of the invention, all metal cords may be identical, oralternatively, different metal cords may be used to provide the impactbeam.

[0024] The metal elements used to provide these metal cords may have adiameter, being a diameter of a radial cross section of the metalelements, which is equal or larger than 100 μm, more preferred largerthan 125 μm e.g. more than 150 μm or even more than 175 μm. All metalelements of a metal cord may have the same diameter, or the diameters ofthe metal elements may differ from each other.

[0025] Preferably, the optical diameter of the metal cord is larger than200 μm, or even larger than 250 μm, such as larger than 300 μm or more.The optical diameter of the metal cord is to be understood as thediameter of the smallest imaginary circle, encompassing the radial crosssection of the metal cord.

[0026] Most preferably steel cords are used to provide the impact beamas subject of the invention. Presently known steel alloys may be used toprovide the steel cords. Preferably, the steel cords are subjected to astress relieving thermal treatment, e.g. by passing the steel cordthrough a high-frequency or mid-frequency induction coil of a lengththat is adapted to the speed of the steel cord during production. It wasobserved that, increasing the temperature to more than 400° C. for acertain period of time, a decrease in tensile strength of the steel cord(a reduction of approximately 10%), but at the same time, an increase ofthe plastic elongation of the cord before rupture of more than 6% may beobtained. Such steel cords are hereafter referred to as stress relievedsteel cords.

[0027] An impact beam as subject of the invention comprises anelastomeric, thermoset or thermoplastic polymer matrix.

[0028] The polymer matrix may comprise polymer material, being athermoplastic or thermoplastic elastomer polymer material. Morepreferred, the polymer material is selected from the group consisting ofpolypropylene, polyethylene, polyamide, polyethylene terephtalate,polybutylene terephtalate, polycarbonate, polyphenylene oxide as well asblends of these materials, or thermoplastic elastomers, e.g. polyamide-or polyolefin-based thermoplastic elastomers such as polyesteramides,polyetheresteramides, polycarbonate-esteramides orpolyether-block-amides.

[0029] Alternatively, the polymer material may be a thermoset polymermaterial, preferably selected from the group consisting of unsaturatedpolyesters, epoxies, vinyl-esters and phenolic resins.

[0030] The polymer matrix may further comprise glass- or C-fibers,polymeric fibers and/or mineral fillers to reinforce the polymer matrix.Fibers can either be random, unidirectional, woven; stitched, chopped,or a combination of those.

[0031] The polymer matrix may have two layers. The first layer,hereafter referred to as ‘embedding layer’ makes contact to the metalcord surfaces. Such embedding layer may be extruded around the metalcord, or several metal cords may be bundles and provided with anembedding layer coating. Alternatively, several metal cords arelaminated in one plane between two foils of polymer material, providinga tape-like structure, hereafter generally referred to as ‘metal cordtape’, or steel cord tapes in case the metal cord tape is provided usingsteel cords.

[0032] Around this metal cord with embedding layer, a second layer,hereafter referred to as volume layer, may be provided, e.g. byextrusion or in a molding process.

[0033] Preferably the polymer material of the embedding layer is anthermoplastic elastomeric or thermoplastic material, preferably athermoplastic polymer material, more preferred being selected from thegroup consisting of polypropylene, polyethylene, polyamide, polyethyleneterephtalate, polybutylene terephtalate, polycarbonate, polyphenyleneoxide as well as blends of these materials, or thermoplastic elastomers,e.g. polyamide- or polyolefin-based thermoplastic elastomers such aspolyesteramides, polyetheresteramides, polycarbonate-esteramides orpolyether-block-amides. Alternatively, the polymer material may be athermoset polymer material, preferably selected from the groupconsisting of unsaturated polyesters, epoxies, vinyl-esters and phenolicresins.

[0034] The polymer material of the volume layer is a thermoplasticelastomeric, thermoset or thermoplastic material, preferably athermoplastic polymer material, more preferred being selected from thegroup consisting of polypropylene, polyethylene, polyamide, polyethyleneterephtalate, polybutylene terephtalate, polycarbonate, polyphenyleneoxide as well as blends of these materials, or thermoplastic elastomers,e.g. polyamide- or polyolefin-based thermoplastic elastomers such aspolyesteramides, polyetheresteramides, polycarbonate-esteramides orpolyether-block-amides. Alternatively, the polymer material may be athermoset polymer material, preferably selected from the groupconsisting of unsaturated polyesters, epoxies, vinyl-esters and phenolicresins.

[0035] This volume layer may further comprise glass- or C-fibers,polymeric fibers and/or mineral fillers to reinforce the volume layer.Fibers can either be random, unidirectional, woven; stitched, chopped,or a combination of those.

[0036] In order to assure a good adhesion between the metal cords andthe polymer material, an adhesion promoter can be applied on the metalcords. Possible adhesion promoters are bifunctional coupling agents suchas silane compounds. One functional group of these coupling agents isresponsible for the binding with the metal or metal oxides; the otherfunctional group reacts with the polymer. More details about thesecoupling agents can be found in the PCT application WO-A-99/20682.

[0037] In order to improve the impact resistance to the required level,the amount of metal cord per section of the impact beam as subject ofthe invention in a direction defined by the height and thickness of theimpact beam, may be chosen.

[0038] Best results are obtained when the metal cords are arranged inone or more planes, parallel to each other and to the impact plane ofthe impact beam, or one or more planes parallel to each other and beingprovided with a curved shape during molding of the impact beam. Thecurvature preferably extends to the side of the impact beam on which theimpact force is to be expected to work. Each plane may be provided bymeans of a metal cord tape or steel cord tape, having embedding layerswhich may be equal or different from each other. Each plane may comprisemetal or steel cords, being equal or different from each other.

[0039] An impact beam as subject of the invention may be manufacturedusing different production techniques.

[0040] A method for providing an impact beam, comprises the steps of

[0041] providing a polymer matrix sheet;

[0042] providing metal cords and/or metal cord tapes;

[0043] heating the polymer matrix sheet;

[0044] bringing the metal cords and/or metal cord tapes and polymermatrix sheet together and providing the metal cords and polymer matrixsheet to a mold;

[0045] molding the metal cords and/or metal cord tapes and polymermatrix sheet, providing an impact beam;

[0046] cooling the impact beam.

[0047] Alternatively, a method for providing an impact beam, comprisesthe steps of

[0048] providing metal cords and/or metal cord tapes;

[0049] extruding polymer material and providing extruded polymermaterial to the metal cords and/or metal cord tapes;

[0050] molding the metal cords and/or metal cord tapes and polymermatrix sheet, providing an impact beam;

[0051] cooling the impact beam.

[0052] As another alternative, a method for providing an impact beam,comprises the steps of

[0053] providing fiber strands and/or reinforcing fabrics;

[0054] providing metal cords and/or metal cord tapes,

[0055] providing uncured or not fully cured polymer material to saidfiber strands and/or reinforcing fabrics and metal cords and/or metalcord tapes by drawing the fiber strands and/or the reinforcing fabricsand the metal cords and/or metal cord tapes, through a bath of uncuredor not fully cured polymer material;

[0056] curing the fiber strands and/or the reinforcing fabrics and themetal cords and/or metal cord tapes and the uncured or not fully curedpolymer material by drawing the fiber strands and/or the reinforcingfabrics and the metal cords and/or metal cord tapes and the uncured ornot fully cured material through a heated pultrusion die, so providing apultruded article;

[0057] cutting pultruded article to lengths, so providing an impactbeam.

[0058] As even an other alternative, a method for providing an impactbeam, comprises the steps of

[0059] providing metal cords and/or metal cord tapes;

[0060] bringing the metal cords and/or metal cord tapes in an extrusionmold and position the metal cords and/or metal cord tapes in the mold;

[0061] providing polymer material in the extrusion mold to provide animpact beam;

[0062] cooling the impact beam.

[0063] Preferably, a polymer matrix sheet, most preferably a Glass MatReinforced Thermoplastic Prepreg is used. The prepreg can either containrandom, unidirectional, woven, stitched or chopped fibers from glass orother materials or combinations of these. Similarly, long fiberthermoplastic compounds can be used comprising chopped strand glassfibers or fibers from other materials This thermoplastic prepreg isheated during a prepreg-heating step, using any kind of oven systemuntil the thermoplastic resin melts. In case of long fiber thermoplasticcompound, an extruder is used to melt the long fiber thermoplasticcompound.

[0064] After the polymer heating step and possibly a metal cord and/ormetal cord tape heating step, the metal cords or metal cord tape and thepolymer material are brought together, usually by providing the polymermaterial e.g. glass mat reinforced thermoplastic prepreg around themetal cord or metal cord tape, and provided to a compression moldingtool. The metal cord or metal cord tape and polymer material togetherare subjected to a molding step. The metal cord or metal cord tape ispositioned in the location of the section of the profile where it isintended to be located to obtain the maximum performance. During theclosing of the mold, the polymer material flows and encapsulates themetal cord or metal cord tape. Possibly, the metal cords or the metalcord tape is provided with a curved shape.

[0065] After the mold is closed, the mold and molded material is cooledduring a cooling step. The mold is re-opened. An impact beam as subjectof the invention is so provided.

[0066] The same molding process can be used, but the oven is replaced byan extruder which produces blobs of polymer material, e.g. hot loftedglass-filled thermoplastics or long fiber thermoplastic compound thatare then manipulated into the tool or mold, together with the metal cordor metal cord tape. After molding, the molded material is cooled.

[0067] Alternatively, glass and/or other fiber strands and metal cordsor metal cord tape may be subjected to a pultrusion process in order toprovide an impact beam as subject of the invention. First fiber strandsand/or reinforcing fabrics and metal cords or metal cord tape areprovided. Uncured or not fully cured polymer material is provided tothese fiber strands and/or reinforcing fabrics and metal cords or metalcord tape by drawing them through a bath of uncured or not fully curedmaterial. Then the fiber strands and/or reinforcing fabrics and cordsand the polymeric polymer material are drawn through a heated pultrusiondie in case of a thermoset material or through a cooling die in case ofthermoplastic material. A pultruded article is so provided. Thepultruded article is cut into lengthsEach cut length is than an impactbeam as subject of the invention. In a second step the impact may bebend or shaped to the desired end shape.

[0068] Alternatively, glass and/or other fiber strands and metal cordsor metal cord tape may be subjected to an over-extrusion process inorder to provide an impact beam as subject of the invention. Metal cordsor metal cord tapes are provided and brought in an extrusion mold andposition in the mold. Polymer material, e.g. thermoplastic material isprovided in the extrusion mold, e.g. by extrusion. After cooling, themold comprises now an impact beam. Possibly, the polymer materialcomprises glass fibers, next to the polymer material, which is or fully,or partially or not cured.

[0069] The impact beam as subject of the invention may further compriseopenings for fixings or mounting other objects. These openings can bebrought into the impact beam by punching, drilling, CNC, laser cuttingor similar techniques, but also by means of inmold punching.

[0070] Preferably, although not always necessarily, the metal cords ormetal cord tapes may also be heated during a metal cord heating step,using any kind of oven or by induction heating.

[0071] Best impact resistance is obtained when the metal cords areembedded in the polymer matrix, having either one or more layers, insuch a way that they have a limited freedom to elongate and/or untwistduring impact. Depending on the type of the metal cord construction, arelatively large amount of impact energy may be absorbed depending onthe impact absorption mechanism, which is typical for that metal cordconstruction.

[0072] High elongation (HE-) cords can absorb impact energy by thestructural deformation of the cords due to movements of strands one toanother in the cord. When structurally deformed filaments are used toprovide the metal cords, also the removing of the structural deformationout of the filaments during elongation of the metal cord will cause anabsorption of the impact energy. In case the metal cord is a stressrelieved steel cord, also the plastic deformation of the filaments willprovide an absorption of impact energy.

[0073] The polymer matrix is preferably bound to the metal cord by meansof a mechanical bond. The polymer matrix may or may not be bound to themetal cords by means of a chemical bond. During a local impact, thepolymer matrix, eventually by means of an embedding layer and a volumelayer, distribute the local force over the full cord length. Thisresults in a full use of the cord's energy absorption abilities hencethe energy to be absorbed by other parts outside the beam is reduced andlocal breakage of the polymer matrix is postponed. The energy absorptionof the cord is either through plastic stretching of the cord itself,through torsional deformation of the cord such as untwisting, or energydissipation in the interface between cord and polymer layer due tofriction when a relative movement of cord versus matrix is taking place.

[0074] If the impact force is such that the local stresses in thepolymer matrix exceed its breaking strength the polymer matrix will fallapart into pieces which still adhere to the metal cords. This fallingapart will absorb a limited amount of impact energy, but after thisfalling apart, the metal cords may elongate to a larger extent and willbe able to absorb to a large extent all impact energy possible untilthey break. Alternatively, when a polymer matrix comprising an embeddinglayer and a volume layer, this volume layer preferably will fall apartfirst by impact. The pieces adhere to the embedding layer and allow theembedding layer and the metal cords to extend to some extent. Thenpossibly the embedding layer, will fall apart but will adhere to themetal cords. These metal cords can then elongate and absorb the impactenergy, which is still left. When in an impact beam several metal cordtapes are used, all parallel to each other, the bond between two metalcord tapes may be broken. Impact energy may then be absorbed due to thefriction caused by the relative movement of both metal cord tapesrelatively to each other.

[0075] An impact beam as subject of the invention may be used to supportsoft bumpers of vehicles such as cars, busses or trucks. It may also beused to improve the impact resistance other elements of the vehicle'scoachwork to impact forces. Impact beam as subject of the invention maybe used to make e.g. doors, frame, bonnet or hood and or cross beamsmore impact resistant. A person skilled in the art understands that theshape of cross sections of an impact beam as subject of the invention,as well as the outer shape of the impact beam, may be adjusted to theuse of the impact beam. The impact beam as subject of the inventionabsorbs the impact energy and protects the other elements of the vehiclefor damaging. The impact beam as subject of the invention also preventsthe particles of the polymer matrix to damage peripheral elements of thevehicle, since the integrity of the impact beam after impact can besecured.

BRIEF DESCRIPTION OF THE DRAWINGS

[0076] The invention will now be described into more detail withreference to the accompanying drawings wherein (See drawings below)

[0077]FIG. 1a being schematically a view-of a cross section of an impactbeam as subject of the invention

[0078]FIG. 1b being schematically a front view of an impact beam assubject of the invention.

[0079]FIG. 2, FIG. 3, FIG. 4a and FIG. 4b being schematically a view ofa cross section of an alternative impact beam as subject of theinvention.

[0080]FIG. 5 being a scheme of a method to provide an impact beam assubject of the invention.

[0081]FIG. 6 shows schematically the use of an impact beam as subject ofthe invention to support a vehicle bumper.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

[0082] An impact beam as subject of the invention is schematically shownin FIG. 1a and FIG. 1b.

[0083] An impact beam 100 has a length 11, which is substantially largerthan the height 12 and the thickness 13 of the impact beam 100. Theembodiment as shown in FIG. 1 has a thickness that is provided by a pairof legs 14 and a main volume 15. The legs 14 may be used to fix theimpact beam to other parts of the object to which it is to be mounted,whereas the main volume 15 (with its thickness 16) will absorb most ofthe impact energy provided by an impact in direction as indicated witharrow 19.

[0084] The main volume 15 and the legs 14 comprise a polymer matrix. Inthe main volume 15, metal cords 18 are present in a directionessentially parallel to the length 11 of the impact beam 100. Preferablyall metal cord are present in one or more planes 10. The metal cords 18used to provide the metal cord tape were 7×7 cords, being a core strandof a filament of 0.21 mm, round which 6 filaments of 0.19 mm aretwisted. Around this core strand, 6 strands are twisted, each strandcomprising a core filament of 0.19 mm around which 6 filaments of 0.175mm are twisted. The matrix is a glass fiber filled polypropylene.

[0085] Alternative embodiments are shown in FIG. 2, FIG. 3 and FIG. 4.

[0086]FIG. 2 shows an impact beam as subject of the invention whichcomprises around metal cord 18 an embedding layer 21 of polymer matrixand a second so-called volume layer 21 of polymer material.

[0087] The metal cord are provided by means of a metal cord tape 23which is provided in a plane essentially perpendicular to the impactdirection 19. The metal cords used to provide the metal cord tape were7×7 cords, being a core strand of a filament of 0.21 mm, round which 6filaments of 0.19 mm are twisted. Around this core strand, 6 strands aretwisted, each strand comprising a core filament of 0.19 mm around which6 filaments of 0.175 mm are twisted. Type polymer material of theembedding layer 20 was a polyolefin based thermoplastic elastomer.

[0088] Type polymer material of volume layer 21 is a glass fiber filledpolypropylene.

[0089]FIG. 3 shows another alternative embodiment of an impact beam assubject of the invention. The metal cords 18 are provided by means oftwo metal cord tapes 31 and 32, which are provided parallel to eachother and essentially parallel to the impact direction 19.

[0090]FIG. 4a shows an improved impact beam as subject of the inventionwhere the legs 41 and main volume 42 are connected to each other bymeans of a transition zone 43. Several metal cord tapes 44 and possibleindividual metal cords 45 may be used to provide impact resistance inboth the main volume 42 or the transition zone 43. FIG. 4b shows another alternative impact beam as subject of the invention. Several metalcord tapes 44 and possible individual metal cords 45 may be used toprovide impact resistance in both the main volume 42 or the legs 41.

[0091] Turning now to a method to provide an impact beam as subject ofthe invention, such method is schematically shown in FIG. 5.

[0092] First a glass mat reinforced thermoplastic prepreg 500 isprovided comprising polymer matrix 501 and possibly glass fiber mat 502(step 50). Also metal cords 503 are provided preferably having anadhesion layer 504 around the surface of the metal cords 503. Mostpreferably the metal cord and adhesion layer are provided as a metalcord tape 505. (step 51).

[0093] As shown in step 52 of FIG. 5, the glass mat reinforcedthermoplastic prepreg 500 is heated to soften the polymer material 501using a furnace 506. glass mat reinforced thermoplastic prepreg may besupported and transported trough the furnace using a transporting meanse.g. a belt 507. After being heated, the hot glass mat reinforcedthermoplastic prepreg is taken of the transporting means as indicatedwith arrow 508, and is provided for addition to the metal cord tape instep 54.

[0094] As shown in step 53 of FIG. 5, the metal cord tape 505 may beheated to soften the polymer material 504 using a furnace 509. metalcord tape may be supported and transported trough the furnace using atransporting means e.g. a belt 510. Possibly after being heated, themetal cord tape is taken of the transporting means as indicated witharrow 508 and is provided for addition to the metal cord tape in step54. A skilled man understands that in case the metal cord or metal cordtape is not to be heated, they may be provided to step 54 with nohandling as in step 53.

[0095] In step 54, the metal cords or metal cord tape 505 and the hotglass mat reinforced thermoplastic prepreg 500 are brought together,e.g. by adding or stacking the different layers one on top of the other.

[0096] The stack 511, comprising the glass mat reinforced thermoplasticprepreg 500 and the metal cord or metal cord tape 505 are provided to amold comprising two parts, being the female mold 512 and the male mold513 (step 55 a). The molds 512 and 513 are closed (step 55 b) and thestack 511 is bend and shaped to the open area inside the closed mold.After this molding (step 55 a and 55 b) the mold and the shaped impactbeam is cooled to a temperature for which the polymer material 501 issolidified (cooling step 56). The impact beam may then be taken out ofthe molds and is ready for further processing, such as quality controlor provision of additional openings.

[0097] An impact beam as subject of the invention is so provided, whichmay be used as support for soft bumpers of vehicles, as shown in FIG. 6.

[0098] An impact beam 61 is connected to peripheral elements 62 of thevehicle caochwork. A soft bumper element 63 may be provided covering theimpact beam 61. when the vehicle strikes an object, an impact force witha direction 64 will apply in as indicated in FIG. 6.

[0099] The metal cord present in the impact beam 61 will adsorb theimpact energy to a large extent, and the polymer material of the impactbeam will adhere to the metal cord to a large extent. This to avoid thatparticles of the polymer material will be projected further towards theparts of the vehicle which are located behind the impact beam.

1. An impact beam comprising a polymer matrix and a metal reinforcingstructure, characterized in that said metal reinforcing structurecomprises metal cords.
 2. An impact beam as in claim 1 said metal cordscomprising metal elements having a diameter of equal or more than 100μm.
 3. An impact beam as in any one of claims 1 to 2, wherein said metalcords have an optical diameter of more than 200 μm.
 4. An impact beam asin any one of claims 1 to 3, wherein said polymer matrix comprisesthermoplastic polymer material.
 5. An impact beam as in any one ofclaims 1 to 4, wherein said polymer matrix comprises polymer materialselected from the group consisting of thermoplastic elastomers,polypropylene, polyethylene, polyamide, polyethylene terephtalate,polybutylene terephtalate, polycarbonate, polyphenylene oxide, andblends of polypropylene, polyethylene, polyamide, polyethyleneterephtalate, polybutylene terephtalate, polycarbonate, polyphenyleneoxide.
 6. An impact beam as in claim 5, said polymer material is apolyamide- or polyolefin-based thermoplastic elastomers.
 7. An impactbeam as in any one of claims 1 to 3, wherein said polymer matrixcomprises thermoset polymer material.
 8. An impact beam as in claim 7,wherein said polymer matrix comprises polymer material selected from thegroup consisting of unsaturated polyesters, epoxies, vinyl-esters andphenolic resins.
 9. An impact beam as in any one of claims 1 to 8,wherein said metal cords being steel cords.
 10. An impact beam as in anyone of claims 1 to 9, wherein said metal cords being essentiallyparallel to each other.
 11. An impact beam as in any one of claims 1 to10, wherein said metal cords being arranged in one or more planes, saidplanes being essentially parallel to each other.
 12. An impact beam asin any one of claims 1 to 11, wherein said polymer matrix comprising atleast two layers, a first layer being present around the surface of saidmetal cords, and a second layer being present around said first layer.13. An impact beam as in claim 12, wherein said first layer being madeout of polymer material selected from the group consisting ofthermoplastic elastomers, polypropylene, polyethylene, polyamide,polyethylene terephtalate, polybutylene terephtalate, polycarbonate,polyphenylene oxide, and blends of polypropylene, polyethylene,polyamide, polyethylene terephtalate, polybutylene terephtalate,polycarbonate, polyphenylene oxide.
 14. An impact beam as in any one ofclaims 11 to 13, wherein said second layer being made out of polymermaterial selected from the group consisting of thermoplastic elastomers,polypropylene, polyethylene, polyamide, polyethylene terephtalate,polybutylene terephtalate, polycarbonate, polyphenylene oxide, andblends of polypropylene, polyethylene, polyamide, polyethyleneterephtalate, polybutylene terephtalate, polycarbonate, polyphenyleneoxide.
 15. An impact beam as in any one of claims 1 to 14, wherein saidmetal cords have a mechanical bond with said polymer matrix
 16. Animpact beam as in any one of claims 1 to 15, wherein said metal cordshave a chemical bond with said polymer matrix.
 17. An impact beam as inany one of claims 1 to 16, wherein said polymer matrix further compriseglass- or C-fibers, polymeric fibers and/or mineral fillers.
 18. Amethod for providing an impact beam, said method comprising the steps ofproviding a polymer matrix sheet; providing metal cords and/or metalcord tapes; heating the polymer matrix sheet; bringing the metal cordsand/or metal cord tapes and polymer matrix sheet together and providingthe metal cords and/or metal cord tapes and polymer matrix sheet to amold; molding the metal cords and/or metal cord tapes and polymer matrixsheet, providing an impact beam; cooling the impact beam.
 19. A methodas in claim 18, said polymer matrix sheet comprising glass fibers.
 20. Amethod for providing an impact beam, said method comprising the steps ofproviding metal cords and/or metal cord tapes; extruding polymermaterial and providing extruded polymer material to said metal cordsand/or metal cord tapes; molding the metal cords and/or metal cord tapesand polymer matrix sheet, providing an impact beam; cooling the impactbeam.
 21. A method for providing an impact beam, said method comprisingthe steps of providing fiber strands and/or reinforcing fabrics;providing metal cords and/or metal cord tapes, providing uncured or notfully cured polymer material to said fiber strands and/or saidreinforcing fabrics and said metal cords and/or metal cord tapes bydrawing said fiber strands and/or said reinforcing fabrics and saidmetal cords and/or metal cord tapes, through a bath of uncured or notfully cured polymer material; curing said fiber strands and/or saidreinforcing fabrics and said metal cords and/or metal cord tapes andsaid uncured or not fully cured polymer material by drawing said fiberstrands and/or said reinforcing fabrics and said metal cords and/ormetal cord tapes and said uncured or not fully cured polymer materialthrough a heated pultrusion die, so providing a pultruded article;cutting pultruded article to lengths, so providing an impact beam.
 22. Amethod for providing an impact beam, said method comprising the steps ofproviding metal cords and/or metal cord tapes; bringing the metal cordsand/or metal cord tapes in an extrusion mold and position the metalcords and/or metal cord tapes in the mold; providing polymer material inthe extrusion mold to provide an impact beam; cooling the impact beam.23. A method as in claim 22, said method further comprising the step ofproviding glass fiber and positioning glass fibers in said extrusionmold.
 24. A method as in any one of claims 20 to 23, said thermoplasticmaterial further comprising glass fibers.
 25. A method as in any one ofclaim 18 to 24, wherein said metal cords are provided as a metal cordtape, comprising metal cords and a polymer matrix around said metalcords.
 26. A method as in any one of claim 18 to 25, wherein said methodfurther comprising the step of heating the metal cords or metal cordtape.
 27. Use of an impact beam as in any one of claims 1 to 17 forsupport of bumpers of vehicles or to improve the impact resistance ofvehicle's coachwork.
 28. Use of an impact beam obtainable by using amethod as in any one of claim 18 to 26 for support of bumpers ofvehicles or to improve the impact resistance of vehicle's coachwork.